Inflammation and in-stent restenosis: the role of serum markers and stent characteristics in carotid artery stenting

The Atherogenic Index of Plasma Predicts Carotid in-Stent Restenosis: Development and Validation of a Nomogram

Purpose

To explore the predictive value of atherogenic index of plasma(AIP) for carotid in-stent restenosis(ISR).

Methods

Patients who underwent carotid artery stenting (CAS) in hospital from January 2016 to January 2021 were retrospectively enrolled. They were randomly divided into training and validation sets. Based on the results of carotid digital subtraction angiography (DSA) during the follow-up period, the patients were divided into ISR group and non-ISR group. The differences of AIP and lipid levels between the two groups were compared. The independent risk factors of ISR and the predictive value of AIP for ISR were analyzed. A nomogram was developed based on the independent risk factors, and the receiver operating characteristic (ROC) curve, the calibration curve and the decision curve analysis were conducted to assess the predictive ability and clinical practicability of the nomogram in both the training set and validation sets.

Results

A total of 361 patients were enrolled, including 98 in the ISR group and 263 in the non-ISR group. In the training set, AIP was significantly higher in the ISR group than in the non-ISR group (P < 0.05) and was independently associated with ISR (OR= 10.912, 95% CI: 2.520-47.248). When AIP was 0.10, it had the highest predictive value for ISR, with a sensitivity of 72. 1% and a specificity of 75.0%. Additionally, hypertension, residual stenosis, symptomatic stenosis and Hcy were also independent risk factors for ISR. The nomogram showed good discrimination performance and clinical practicability in both the training set (AUC = 0.827) and the validation set (AUC = 0.880).

Conclusion

AIP was an independent risk factor for ISR and was closely related to ISR. The nomogram developed by AIP and other variables had good predictive ability and clinical practicability for ISR.

Recanalization of chronic long-segment occlusion of the internal carotid artery with endovascular and hybrid surgery

To investigate the effect of endovascular and/or hybrid surgical recanalization on chronic long-segment occlusion of the internal carotid artery (ICA) and the effect of occlusion location on the recanalization rate and prognosis, 87 patients with chronic ICA occlusion treated with endovascular approach only or hybrid surgery were retrospectively enrolled. The duration of ICA occlusion ranged from 21 to 360 days (median 30). Type I occlusion (from the neck to below the cavernous segment) consisted of 46 (52.8%) patients while type II (from the neck to above the clinoid segment) of 41 (47.1%). Hybrid surgery was performed in 44 (50.6%) patients while endovascular recanalization only was conducted in the other 43 (49.4%). In all patients, the success rate of recanalization was 93.0% (40/43) for the endovascular approach and 95.5% for the hybrid surgical approach. In patients with type I occlusion, endovascular recanalization only was performed in 22 (47.8%) patients and hybrid surgery in 24 (52.2%), resulting in successful recanalization in all patients (100%). In patients with type II occlusion, the success rate of recanalization was 85.7% (18/21) for the endovascular approach only but 90% (18/20) for the hybrid surgery. The total success rate of recanalization was 94.3% (82/87) for all patients, 100% for type I occlusion, and 87.8% for type II occlusion. No significant (P = 0.12) differences existed in the recanalization rate between groups I and II. Clinical follow-up was performed in 82 (94.3%) patients 6-39 months (mean 16) after the surgery. Re-occlusion occurred in 0 in group I but in four (9.8%) in group II. The mRS was good with 0-2 in 38 (82.6%) patients in group I and in 27 (75%) patients in group II, with no significant (P = 0.78) difference. In conclusion, chronic long-segment ICA occlusion can be safely and efficiently recanalized with the endovascular and hybrid surgery. The location of ICA occlusion may have a critical role in determining the recanalization rate, and careful evaluation of the occlusion location may be helpful in increasing the prognosis of recanalization.

The preoperative triglyceride-glucose index has a positive effect on predicting the risk of short-term restenosis after carotid artery stenting: a retrospective cohort study

Background

Increasing evidence suggests that insulin resistance is linked to cardiovascular disease and atherosclerosis. The triglyceride-glucose (TyG) index has proven to be a convincing marker to quantitatively evaluate insulin resistance. However, there is no relevant information about the relationship between the TyG index and restenosis after carotid artery stenting.

Methods

A total of 218 patients were enrolled. Carotid ultrasound and computed tomography angiography were used to evaluate in-stent restenosis. A Kaplan-Meier analysis and Cox regression method were performed to analyze the correlation between TyG index and restenosis. Schoenfeld residuals were used to determine the proportional-hazards assumption. A restricted cubic spline method was used to model and visualize the dose-response relationship between the TyG index and the risk of in-stent restenosis. Subgroup analysis was also performed.

Results

Thirty-one participants (14.2%) developed restenosis. The preoperative TyG index had a time-varying effect on restenosis. Within 29 months post-surgery, an increasing preoperative TyG index was linked to a significant increased risk of restenosis (hazard ratio: 4.347; 95% confidence interval 1.886-10.023). However, after 29 months, the effect was decreased, although not statistically significant. The subgroup analysis showed that the hazard ratios tended to be higher in the age ≤ 71 years subgroup (p < 0.001) and participants with hypertension (p < 0.001).

Conclusion

The preoperative TyG index was significantly associated with the risk of short-term restenosis after CAS within 29 months post-surgery. The TyG index may be employed to stratify patients based on their risk of restenosis after carotid artery stenting.

Effects of stent shape on focal hemodynamics in intracranial atherosclerotic stenosis: A simulation study with computational fluid dynamics modeling

Background and aims

The shape of a stent could influence focal hemodynamics and subsequently plaque growth or in-stent restenosis in intracranial atherosclerotic stenosis (ICAS). In this preliminary study, we aim to investigate the associations between stent shapes and focal hemodynamics in ICAS, using computational fluid dynamics (CFD) simulations with manually manipulated stents of different shapes.

Methods

We built an idealized artery model, and reconstructed four patient-specific models of ICAS. In each model, three variations of stent geometry (i.e., enlarged, inner-narrowed, and outer-narrowed) were developed. We performed static CFD simulation on the idealized model and three patient-specific models, and transient CFD simulation of three cardiac cycles on one patient-specific model. Pressure, wall shear stress (WSS), and low-density lipoprotein (LDL) filtration rate were quantified in the CFD models, and compared between models with an inner- or outer-narrowed stent vs. an enlarged stent. The absolute difference in each hemodynamic parameter was obtained by subtracting values from two models; a normalized difference (ND) was calculated as the ratio of the absolute difference and the value in the enlarged stent model, both area-averaged throughout the arterial wall.

Results

The differences in focal pressure in models with different stent geometry were negligible (ND<1% for all cases). However, there were significant differences in the WSS and LDL filtration rate with different stent geometry, with ND >20% in a static model. Observable differences in WSS and LDL filtration rate mainly appeared in area adjacent to and immediately distal to the stent. In the transient simulation, the LDL filtration rate had milder temporal fluctuations than WSS.

Conclusions

The stent geometry might influence the focal WSS and LDL filtration rate in ICAS, with negligible effect on pressure. Future studies are warranted to verify the relevance of the changes in these hemodynamic parameters in governing plaque growth and possibly in-stent restenosis in ICAS.

Increased neutrophil-to-lymphocyte ratio is associated with higher incidence of acute kidney injury and worse survival after transcatheter aortic valve implantation

BACKGROUND

Although considered a minimally invasive procedure, transcatheter aortic valve implantation (TAVI) generates an inflammatory response which is related to post-procedural complications including acute kidney injury (AKI). The aim of the present study was to analyse the association between simple, easily available post-operative morphological parameters of inflammatory status such as neutrophil-to-lymphocyte ratio (NLR) and AKI as well as post-discharge survival.

METHODS

The study group was comprised of 203 consecutive patients (102 females and 101 males, mean age 78 ± 6.9 years) who underwent TAVI between January 2013 and March 2017. Demographic and clinical data were collected. Baseline and subsequent post-procedural blood samples (8, 24, 48, 72 at discharge) were taken. Blood morphology (including NLR) and creatinine concentration were assessed. Long-term survival was also analyzed.

RESULTS

Seventy-four (36.5%) patients developed AKI. Baseline morphological parameters did not differ between subject with and without AKI. Those reflecting post-procedural inflammatory response, including leucocytes, neutrophils and NLR increased significantly following TAVI in both subgroups and the rise was more pronounced in AKI patients (p < 0.001). A comparison of Kaplan-Meier curves for patients with the lowest (NLR 1; below 25th percentile) and highest NLR (NLR 3; above 75th) revealed a significant difference in the log-rank test (p = 0.049). Estimated probability of 1-, 2- and 5-year survival were 100% vs. 79%, 94% vs. 77% and 75% vs. 46%, respectively in subgroup NLR 1 and NLR 3.

CONCLUSIONS

Inflammatory response after TAVI, estimated by means of NLR, is more pronounced in patients with AKI. A higher value of NLR is associated with a lower probability of long-term survival after TAVI.

A critical appraisal of humanized alternatives to fetal bovine serum for clinical applications of umbilical cord derived mesenchymal stromal cells

OBJECTIVE

The study is aimed to verify the possibility of using humanized alternatives to fetal bovine serum (FBS) such as umbilical cord blood plasma (CBP) and AB⁺ plasma to support the long-term growth of mesenchymal stromal cells (MSCs) derived from the umbilical cord. We hypothesized that umbilical CBP would be a potential substitute to FBS, especially for small scale autologous clinical transplantations.

METHODS

The MSCs were cultured for six consecutive passages to evaluate xeno-free media's ability to support long-term growth. Cell proliferation rates, colony-forming-unit (CFU) efficiency and population doublings of expanded MSCs, were investigated. Ex vivo expanded MSCs were further characterized using flow cytometry and quantitative PCR. The impact of cryopreservation and composition of cryomedium on phenotype, viability of MSC was also assessed.

RESULTS

Our results on cell proliferation, colony-forming unit efficiency suggested that the expansion of the cells was successfully carried out in media supplemented with humanized alternatives. MSCs showed lower CFU counts in FBS (~ 25) than humanized alternatives (~ 35). The gene expression analysis revealed that transcripts showed significant differential expression by two to three folds in the FBS group compared with MSCs grown in medium with humanized alternatives (p < 0.05). In addition, MSCs grown in a medium with FBS had more osteogenic activity, a signature of unwanted differentiation. The majority of ex vivo expanded MSCs at early and late passages expressed CD44⁺, CD73⁺, CD105⁺, CD90⁺, and CD166⁺ in all the experimental groups tested (~ 90%). In contrast to the other MSC surface markers, expression levels of STRO-1⁺ (~ 21-10%) and TNAP⁺ (~ 29-11%) decreased with the increase in passage number for MSCs cultured in a FBS-supplemented medium (p < 0.05).

CONCLUSION

Our results established that CBP supported culture of umbilical cord tissue-derived MSCs and is a safer Xeno free replacement to FBS. The use of CBP also enables the storage of umbilical cord tissue derived MSCs in patient-specific conditions to minimize adverse events if cells are delivered directly to the patient.

Long-Term Risk Factors for Intracranial In-Stent Restenosis From a Multicenter Trial of Stenting for Symptomatic Intracranial Artery Stenosis Registry in China

Background: For patients with symptomatic intracranial artery stenosis (sICAS), endovascular treatment has been shown to be feasible and safe in recent studies. However, in-stent restenosis (ISR) risks the recurrence of ischemic stroke. We attempt to elucidate the risk factors for ISR. Methods: We retrospectively analyzed 97 patients with sICAS from a prospective registry trial that included 20 centers from September 2013 to January 2015. Cases were classified into the ISR≥ 50% group or the ISR < 50% group. The baseline characteristics and long-term follow-up were compared between the two groups. Binary logistic regression analyses were identified as an association between ISR and endovascular technique factors. Results: According to whether ISR was detected by CT angiography, 97 patients were divided into the ISR group (n = 24) and the non-ISR group (n = 73). The admission baseline features and lesion angiography characteristics were similar, while plasma hs-CRP (mg/L) was higher in the ISR≥ 50% group at admission (8.2 ± 11.4 vs. 2.8 ± 4.1, p = 0.032). Binary logistic regression analysis identified the longer stents (adjusted OR 0.816, 95% CI 0.699-0.953; p = 0.010), balloon-mounted stents (adjusted OR 5.748, 95% CI 1.533-21.546; p = 0.009), and local anesthesia (adjusted OR 6.000, 95% CI 1.693-21.262; p = 0.006) as predictors of ISR at the 1-year follow-up. Conclusions: The longer stents, balloon-mounted stents implanted in the intracranial vertebral or basilar artery, and local anesthesia were significantly associated with in-stent restenosis. Further studies are required to identify accurate biomarkers or image markers associated with ISR in ICAS patients. Clinical Trial Registration: www.ClinicalTrials.gov, identifier: NCT01968122.

CYP2C19*2 genetic polymorphism and incidence of in-stent restenosis in patients on clopidogrel: a matched case-control study

OBJECTIVES

The cytochrome P450 2C19*2 (CYP2C19*2) genetic polymorphism is associated with reduced clopidogrel bioactivation, increasing the risk of atherothrombotic complications after percutaneous coronary intervention (PCI). In-stent restenosis (ISR) is a complication that limits the long-term prognosis of PCI. The aim was to investigate the association between presence of the CYP2C19*2 allele and ISR within one-year after PCI in patients prescribed dual antiplatelet therapy with aspirin and clopidogrel.

METHODS

Sixty patients with angiographically-confirmed drug eluting stent (DES)-ISR within 12 months post-PCI when on DAPT with aspirin and clopidogrel were retrospectively identified (Cases). Another 60 patients with no documented ISR post-PCI in the study period (Controls) were case-matched for age, gender, ethnicity, diabetes mellitus and estimated glomerular filtration rate value, and were invited for CYP2C19*2 genotyping. The association between presence of the CYP2C19*2 allele and ISR was analysed using the Fisher's Exact test and binary logistic regression.

RESULTS

Twenty-six (43.3%) cases and 5 (8.3%) controls were carriers of one or two CYP2C19*2 alleles. As to non-carrier status of the CYP2C19*2 allele, 34 (56.7%) cases and 55 (91.7%) controls were identified. The association between CYP2C19*2 carrier status and DES-ISR within one-year post-PCI was statistically significant (p<0.001) in both the univariate and multivariate analysis.

CONCLUSIONS

The proportion of patients who were carriers of one or two CYP2C19*2 alleles who presented with DES-ISR within one-year post-PCI while on clopidogrel was significantly higher compared to patients with no documented ISR.

The association of preprocedural C-reactive protein/albumin ratio with in-stent restenosis in patients undergoing iliac artery stenting

Introduction: In-stent restenosis (ISR) still constitutes a major problem after percutaneous vascular interventions and the inflammation has a pivotal role in the pathogenesis of such event. The C-reactive protein/albumin ratio (CAR) is a newly identified inflammatory biomarker, and it may be used as an indicator to predict ISR in subjects with coronary artery stenting. In light of these data, our main objective was to investigate the relationship between the preprocedural CAR and ISR in patients undergoing successful iliac artery stent implantation.

Methods: In total, 138 consecutive patients who had successful iliac artery stent implantation in a tertiary heart center between 2015 and 2018 were enrolled in the study. The study population was categorized into two groups; patients with ISR and those without ISR during follow-up. The CAR was determined by dividing CRP by serum albumin.

Results: In the multivariable regression analysis; the CAR (HR: 2.66, 95% CI: 1.66-4.25, P < 0.01), stent length (HR: 1.01, 95% CI: 0.99-1.02, P = 0.04), and HbA1c levels (HR: 1.22, 95% CI: 0.99-1.51, P = 0.04) were independently related with ISR. A receiver operating curve analysis displayed that the CAR value of >0.29 predicted ISR with sensitivity of 97.5% and specificity of 88.8% (AUC 0.94, P < 0.01).

Conclusion: Our findings provide evidence that the CAR may be an applicable inflammatory biomarker in predicting ISR in subjects undergoing iliac artery stenting for the treatment of peripheral artery disease (PAD). Also, the stent length and poor glycemic control were found to be associated with ISR.

Neutrophil-to-lymphocyte ratio and platelet-to-lymphocyte ratio: novel markers for the diagnosis and prognosis in patients with restenosis following CAS

Aim: In this study, we investigated the effect of neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio on restenosis status in patients undergoing carotid angioplasty stenting (CAS). Methodology & results: Clinical imageology and receiver operating characteristic analysis were utilized to study the prognostic significance of NLRs/platelet-to-lymphocyte ratios and their correlation with survival. NLR of restenosis (+) patients was evidently increased after the CAS procedures, while the NLR of restenosis (-) patients before the CAS procedures being the lowest. Area under the curve of pre-CAS NLR or/and post-CAS NLR were all evidently higher than 50%. Also, restenosis incidence was the highest in patients with both high pre-CAS and high post-CAS values. Conclusion: Therefore, NLR can be utilized as an independent prognostic indicator to predict the incidence of restenosis after CAS procedures.

LIM-only protein FHL2 attenuates inflammation in vascular smooth muscle cells through inhibition of the NFκB pathway

Despite the advent of new-generation drug-eluting stents, in-stent restenosis remains a significant problem in patients with coronary artery disease. In- stent restenosis is defined as the gradual re-narrowing of a stented coronary artery lesion due to arterial damage with subsequent local inflammation of the vessel wall and excessive growth of the vascular smooth muscle cells (vSMCs). Four-and-a-half LIM-domain protein 2 (FHL2) is a scaffold protein involved in regulating vSMC function and inflammation. Previously we have demonstrated that FHL2 prevents vSMC proliferation in a murine carotid artery ligation model. However, the effect of FHL2 on the inflammatory response of the vSMCs is not investigated. Therefore, we studied the inflammatory response in the vessel wall of FHL2-deficient (-KO) mice after carotid artery ligation. We found that circulating cytokines and local macrophage infiltration in the ligated carotid vessels were increased in FHL2-KO mice after carotid artery ligation. Moreover, FHL2-KO vSMCs showed increased secretion of cytokines such as SDF-1α and RANTES, and enhanced activation of the NFκB pathway. Finally, we found that blocking the NFκB signalling pathway abrogated this pro-inflammatory state in FHL2-KO vSMCs. Taken together, our results demonstrate that FHL2 decreases the inflammatory response of vSMCs through inhibition of the NFkB-signalling pathway.

The number of stents was an independent risk of stent restenosis in patients undergoing percutaneous coronary intervention

Percutaneous coronary intervention (PCI) is one of the most effective therapies for coronary artery disease, but stent restenosis remains an important clinical challenge. The studies about the independent effect of the number of stents on stent restenosis were limited.The purpose was to identify the independent effect of the number of stents on stent restenosis.A retrospective cohort study of data reuse.From July 2009 to August 2011, a total of 2338 cases met the inclusion and exclusion criteria.The univariate analysis showed that the number of stents was a risk of stent restenosis, the OR value was 1.30 (95% CI:1.15 to 1.47, P < .001). The multi-factor regression analysis also showed that the number of stents was an independent risk of stent restenosis, the adjusted OR value was 1.38 (95% CI: 1.15 to 1.66, P < .001).Compared with 1-2 stents, the adjusted OR values of 3-5 stents and more than 6 stents were respectively 2.20 (95% CI: 1.24 to 3.90, P = .007) and 5.33 (95% CI: 1.89 to 15.08, P = .002), and the trend adjusted OR values was 2.26 (95% CI: 1.43 to 3.59, P < .001).The subgroup analysis of multi-factor regression analysis showed that when patients with the following conditions: 50 < Age, female, non-DES or SES, the risk of stent restenosis increased obviously.The number of stents was an independent risk of stent restenosis in patients undergoing PCI, especially for patients with the following conditions: 2<the number of stents, 50 < age, female, Non-DES (Drug-eluting stents) or SES (sirolimus-eluting stent).

Prevention of neointimal hyperplasia induced by an endovascular stent via intravenous infusion of mesenchymal stem cells

OBJECTIVE

In-stent restenosis after percutaneous transluminal angioplasty and stenting (PTAS) due to neointimal hyperplasia is a potential cause of clinical complications, including repeated revascularization and ischemic events. Neointimal hyperplasia induced by an inflammatory response to the stent strut may be a possible mechanism of in-stent restenosis. Intravenous infusion of bone marrow-derived mesenchymal stem cells (MSCs) has been reported to show therapeutic efficacy for cerebral stroke, presumably by an antiinflammatory effect. This study aimed to determine whether MSCs can reduce or prevent neointimal hyperplasia induced by an endovascular stent.

METHODS

In this study, two types of bare metal stents were deployed using a porcine (mini-pig) model. One stent was implanted in the common carotid artery (CCA), which is considered quite similar to the human CCA, and the other was inserted in the superficial cervical artery (SCA), which is similar in size to the human middle cerebral artery. Angiographic images, intravascular ultrasound (IVUS) imaging, and microscopic images were used for analysis.

RESULTS

Angiographic images and IVUS studies revealed that intravenous infusion of MSCs immediately after deployment of stents prevented in-stent stenosis of the CCA and SCA. Histological analysis also confirmed that inflammatory responses around the stent struts were reduced in both the stented CCA and SCA in the mini-pig.

CONCLUSIONS

Intravenous infusion of MSCs inhibited the inflammatory reaction to an implanted stent strut, and prevented progressive neointimal hyperplasia in the stented CCA and SCA in a porcine model. Thus, MSC treatment could attenuate the recurrence of cerebral ischemic events after stenting.

Influence of stenting with open-cell stents vs close-cell stents on the outcomes of patients with bilateral carotid stenosis

BACKGROUND

Carotid artery stenting (CAS) is an effective way to prevent stroke in patients with severe carotid stenosis. However, several studies comparing the outcomes of stenting with open-cell stents (OCS) vs closed-cell stents (CCS) have yielded inconclusive results. This study aimed to compare the outcomes of CAS with OCS vs CCS in the same patients.

METHODS

From year 2000 to 2016, we included 52 patients with severe bilateral carotid stenosis who underwent OCS deployment in one artery and CCS deployment in the contralateral artery. Stents were selected according to arterial anatomy and lesion morphology, and the peri-procedural and long-term outcomes of treatment with OCS vs CCS, were compared in terms of rates of ischemic spot development on early post-procedural diffusion-weighted imaging (ISDWI), in-stent restenosis (ISR), and recurrent stroke.

RESULTS

After stenting with OCS vs CCS, the number (rate) of arteries with no lesion, < 5 lesions, and ≥ 5 lesions on DWI was 9 (32%) vs 8 (27%), 8 (29%) vs 17 (57%), and 11 (39%) vs 5 (17%) (p = .10); number (rate) of arteries with 0%, < 50%, and >50% ISR was 34 (65%) vs 34 (65%), 9 (17%) vs 11 (21%), and 9 (17%) vs 7 (13%) (p = .71); number (rate) of recurrent strokes after CAS was 2 (4%) vs 0 (0%).

CONCLUSION

The rates of peri-procedural cerebral ischemic insult, long-term stent patency, and stroke recurrence indicate that no one carotid stent cell design is superior to the other. We suggest both OCS and CCS are reasonable options for the treatment of severe carotid stenosis.

Neutrophil to Lymphocyte Ratio as a Predictor of Restenosis After Angioplasty and Stenting for Asymptomatic Carotid Stenosis

The inflammatory response plays a vital role in the development of in-stent restenosis (ISR) after carotid angioplasty and stenting (CAS). The neutrophil to lymphocyte ratio (NLR) has been suggested as a sensitive inflammatory marker. We explored the association between NLR and ISR in CAS patients. A total of 427 patients who underwent CAS were enrolled. Neutrophil to lymphocyte ratio was measured before the procedure. Clinical examination and radiographic evaluation were performed at 6 months and annually after the procedure. In-stent restenosis was defined as ≥50% stenosis in the treated lesion. Cox regression was used to identify predictors of ISR after CAS. Of the 459 arteries (in 427 patients) with CAS, 72 (15.7%) were identified with ISR during a mean follow-up of 14.6 (19.1) months (range, 0.7-120.7 months). Increased NLR (≥2.13) was significantly related to ISR in patients with asymptomatic stenosis ( P = .001). However, significance was not observed in symptomatic stenosis. On multivariate analysis, baseline NLR ≥ 2.13 (hazard ratio [HR], 2.74; 95% confidence interval [CI], 1.46-5.14), smoking (HR, 1.99; 95% CI, 1.11-3.58), residual stenosis (HR, 1.12; 95% CI, 1.09-1.15), and baseline glucose level (HR, 1.01; 95% CI, 1.01-1.02) were associated with ISR. Elevated NLR may be a predictor of ISR after CAS for asymptomatic stenosis.

Prognostic Value of Type D Personality for In-stent Restenosis in Coronary Artery Disease Patients Treated With Drug-Eluting Stent

OBJECTIVE

To evaluate the predictive value of Type D personality on in-stent restenosis (ISR) rates at 1 and 2 years post-percutaneous coronary intervention (PCI) in patients with coronary artery disease.

METHODS

Consecutive patients with coronary artery disease who underwent PCI for drug-eluting stents (n = 173) completed the Type D Scale-14 (DS14) at baseline. Follow-up coronary angiographic evaluation was routinely planned at 1 and 2 years after the procedure.

RESULTS

Follow-up coronary angiography was performed in 159 and 112 patients at 1 and 2 years post-PCI, respectively. On multivariate analysis, Type D personality was found to be an independent predictor of ISR at 1 year (odds ratio [OR] = 2.67, 95% confidence interval [CI] = 1.16-6.14, p = .021) and 2 years (OR = 4.92, 95% CI = 1.82-9.60, p = .017) after adjusting for cardiovascular risk factors. However, Type D did not predict ISR when the analysis was performed using the interaction between negative affectivity and social inhibition. The main effect of negative affectivity emerged as a significant risk factor for 1-years (OR = 4.22, 95% CI = 1.18-7.86, p = .034) and 2-year ISR (OR = 6.93, 95% CI = 2.25-11.50, p = .016).

CONCLUSIONS

In this study, Type D personality was an independent predictor of ISR at 1 and 2 years post-PCI; the association strengthened with time. The negative affectivity component seems to drive the relationship between Type D and ISR over time. Our findings provide new insights into the mechanisms involved in the association between Type D and adverse clinical outcomes of PCI.

Calcification in original plaque and restenosis following carotid artery stenting

Background:

The relationship between calcification in primary plaque and recurrent stenosis after carotid artery stenting (CAS) is not established, but an inverse association with restenosis following carotid endarterectomy (CEA) has been suggested.

Methods:

We retrospectively analyzed 75 plaques of 109 consecutive CAS with regard to calcification, using the calcium score and shape, location, and other characteristics of original plaques together with stenting-related factors. CAS was performed in a standard fashion with an embolic protection device. Greater-than-moderate restenosis (≥50%) was assessed by peak systolic velocity (PSV) with duplex ultrasonography (≥130 cm/s, internal/common carotid or distal/proximal PSV ratio ≥2.0).

Results:

Univariate analysis revealed percentages of dyslipidemia treated with statins (P = 0.03), calcification in distal ICA (P = 0.02), and immediate residual stenosis (P = 0.02) were significantly higher in patients with greater-than-moderate restenosis, whereas calcification in carotid bulb and usage of open-cell stent were rather less frequent (P < 0.001 and P = 0.02, respectively). Multivariate logistic regression analysis showed that rarity of calcification in carotid bulb was a sole independent predictor for greater-than-moderate recurrent carotid stenosis 1 year after CAS (OR = 0.21, CI = 0.06–0.77, P = 0.02).

Conclusions:

Calcium score was not significantly related to restenosis at 1 year after CAS, as was previously found following CEA, though scarcity of calcification in carotid bulb was suggested as a predictor of in-stent restenosis. Compared to post-CEA restenosis, carotid plaque calcification may be inversely but tenuously associated with recurrent stenosis 1 year post-CAS. No other stenting factors (e.g., stent design, pre-/post-dilation, or protection devices) showed a significant association with recurrent stenosis post-CAS.

Decreased PPAR-γ expression after internal carotid artery stenting is associated with vascular lesions induced by smooth muscle cell proliferation and systemic inflammation in a minipig model

Vascular restenosis after stenting is known to be largely mediated by proliferation of vascular smooth muscle cells. Recently, peroxisome proliferator-activated receptor gamma (PPAR-γ) has been implicated as a regulator of cellular inflammatory responses, and the PPAR-γ agonist rosiglitazone (ROSI) has been shown to attenuate atherosclerosis formation. However, whether ROSI can inhibit neointimal formation by regulating the inflammatory response and inhibiting vascular smooth muscle hyperplasia after stenting-induced injury remains to be clarified. Accordingly, in this study, 10 minipigs were randomly divided into two groups: the stenting group (n = 5) and the ROSI group (n = 5). Morphometric analysis was conducted for the stented arteries. The protein expressions of PPAR-γ and smooth muscle 22-alpha (SM22α) were analyzed by immunohistochemistry and western blotting, and the serum interferon-γ and interleukin-10 levels were measured by enzyme-linked immunosorbent assay. Three months after implantation, morphometric analysis revealed that administration of ROSI (0.5 mg/kg/d, continuous administration for 90 days) resulted in significant reductions of luminal stenosis, the neointimal area, and neointimal thickness, as compared to the stenting groups. The expression of PPAR-γ and the PPAR-γ/SM22α ratio in the ROSI group were higher than in the stenting group. Furthermore, the serum interferon-γ and interleukin-10 levels were found to be increased and to reach peak levels at 4 h and 7 days after stenting, respectively, after which both declined. However, ROSI treatment resulted in decreased interferon-γ and increased interleukin-10 levels after stenting. In both groups, the cytokine levels returned to the baseline levels on day 56 after stenting. Taken together, these results suggest that ROSI can reduce neointimal formation after stenting by inhibiting the local and systemic inflammatory responses as well as vascular smooth muscle hyperplasia.

Artificial Zinc-Finger Transcription Factor of A20 Suppresses Restenosis in Sprague Dawley Rats after Carotid Injury via the PPARα Pathway

The inhibition of inflammation and vascular smooth muscle cell (VSMC) proliferation is an ideal strategy to suppress intimal hyperplasia after percutaneous transluminal angioplasty (PTA). Evidence has indicated that overexpression of A20 suppresses neointima formation, but its low transfection efficiency limits its application. Hence, we upregulated A20 expression via transfection of rAd.ATF (recombinant adenovirus vector of artificial transcription factor) and rAd.A20 in rat carotid arteries after balloon dilatation (in vivo) and isolated VSMCs (in vitro). In vivo, we found that after rAd.ATF and rAd.A20 transfection, A20 expression was markedly increased, whereas proliferating cell nuclear antigen (PCNA) and nuclear factor κB p65 (NF-κBp65) protein levels were significantly decreased, and intimal hyperplasia and secretion of proinflammatory factors were significantly reduced when compared with empty vector and saline control groups. Most importantly, the rAd.ATF-treated group showed more significant inhibition on intimal hyperplasia and expression of PCNA than the rAd.A20-treated group. In vitro, compared with the control group, transfection of rAd.ATF and rAd.A20 significantly increased A20 expression, which upregulated the proliferator-activated receptor (PPAR) level for both mRNA and protein, and reduced migration and proliferation of VSMCs and lipopolysaccharide (LPS)-induced inflammation. Furthermore, the PPARα agonist GW6471 could partially restore the effect of A20 on VSMCs. Our findings indicate that the ATF of A20 inhibits neointimal hyperplasia and, therefore, constitutes a novel potential alternative to prevent restenosis.

Restenosis after carotid artery stenting

As a common etiology for ischemic stroke, atherosclerotic carotid stenosis has been targeted by vascular surgery since 1950s. Compared with carotid endarterectomy, carotid angioplasty and stenting (CAS) is almost similarly efficacious and less invasive. These advantages make CAS an alternative in treating carotid stenosis. However, accumulative evidences suggested that the long-term benefit-risk ratio of CAS may be decreased or even neutralized by the complications related to in-stent restenosis (ISR). Therefore, investigating the mechanisms and identifying the influential factors of ISR are of vital importance for improving the long-term outcomes of CAS. As responses to intrinsic and extrinsic injuries, intimal hyperplasia and vascular smooth muscle cell proliferation have been regarded as the principle mechanisms for ISR development. Due to the lack of consensus-based definition and consistent follow-up protocol, the reported incidences of ISR after CAS varied widely among studies. These variations made the inter-study comparisons of ISR largely illogical. To eliminate restenosis after CAS, both surgery and endovascular procedures have been attempted with promising results. For preventing ISR, drug-eluting stents and antiplatelets have been proposed as potential solutions.

Anatomical and Technical Factors Influence the Rate of In-Stent Restenosis following Carotid Artery Stenting for the Treatment of Post-Carotid Endarterectomy Stenosis

Background

Carotid artery stenting (CAS) has been advocated as an alternative to redo surgery for the treatment of post-carotid endarterectomy (CEA) stenosis. This study analyzed the efficacy of CAS for post-CEA restenosis, focusing on an analysis of technical and anatomical predictive factors for in-stent restenosis.

Methods

We performed a retrospective monocentric study. We included all patients who underwent CAS for post-CEA restenosis at our institution from July 1997 to November 2013. The primary endpoints were the technical success, the presence of in-stent restenosis >50% or occlusion, either symptomatic or asymptomatic, during the follow-up period, and risk factors for restenosis. The secondary endpoints were early and late morbidity and mortality (TIA, stroke, myocardial infarction, or death).

Results

A total of 153 CAS procedures were performed for post-CEA restenosis, primarily because of asymptomatic lesions (137/153). The technical success rate was 98%. The 30-day perioperative stroke and death rate was 2.6% (two TIAs and two minor strokes), and rates of 2.2% (3/137) and 6.2% (1/16) were recorded for asymptomatic and symptomatic patients, respectively. The average follow-up time was 36 months (range, 6–171 months). In-stent restenosis or occlusion was observed in 16 patients (10.6%). Symptomatic restenosis was observed in only one patient. We found that young age (P = 0.002), stenosis > 85% (P = 0.018), and a lack of stent coverage of the common carotid artery (P = 0.006) were independent predictors of in-stent restenosis.

Conclusion

We identified new risk factors for in-stent restenosis that were specific to this population, and we propose a technical approach that may reduce this risk.

Role of red blood cell distribution in predicting drug-eluting stent restenosis in patients with stable angina pectoris after coronary stenting

BACKGROUND

It has been reported that increased red blood cell distribution width (RDW) predicts adverse events in cardiovascular disease and in patients undergoing percutaneous coronary intervention. However, the role of serum RDW levels in drug-eluting stent (DES) restenosis remains unclear. We aimed to investigate the relationship between serum RDW levels and in-stent restenosis (ISR) after coronary stenting with DES in stable angina pectoris (SAP) patients.

MATERIALS AND METHODS

A total of 293 consecutive chronic SAP patients with coronary DES implantation were enrolled in this study. The ISR was analyzed by coronary angiography analysis at a mean follow-up of 8 months. According to whether ISR was detected, patients were divided into two groups: the ISR group (n=45) and the non-ISR group (n=247). Serum RDW was assessed both at admission and at the 8-month follow-up in all patients. Standard medication was continued throughout the investigation period.

RESULTS

Baseline characteristics of the two groups were similar. Patients in the ISR group had significantly higher RDW levels compared with patients in the non-ISR group both at admission and at follow-up (P<0.01, respectively). Furthermore, the ISR group had significantly longer stent length and lower stent diameter compared with the non-ISR group (P<0.01, respectively). In a multivariate analysis, diabetes mellitus, current smoking, RDW levels, C-reactive protein levels, stent length, and stent diameter were associated independently with ISR.

CONCLUSION

Serum RDW level may independently predict ISR at both admission and follow-up in SAP patients with coronary DES implantation, which indicates that a chronic inflammatory response might be involved in the pathogenesis of ISR.

The Effect of Stent Cell Geometry on Carotid Stenting Outcomes

PURPOSE

The aim of this study was to investigate the effect of stent cell geometry on midterm results of carotid artery stenting (CAS).

MATERIALS AND METHOD

One hundred fifty-five patients underwent CAS between February 2010 and December 2012. Ninety-one open- and 84 closed-cell stents were used in this non-randomized, retrospective study. Periprocedural complications were defined as the ones happened during the procedure or within 30 days afterwards. Starting from the 6th month after the procedure, in-stent restenosis was detected with multidetector computed tomography angiography and classified into four groups from focal restenosis to occlusion.

RESULTS

Eleven complications were encountered in the periprocedural period (four on the open- and seven on the closed-cell group). Total complication rate was 6.3% (11/175). No significant difference was detected in terms of periprocedural complications between two groups (p = 0.643). There was statistically significant difference between stent design groups in regard to radiological findings (p = 0.002). Sixteen of open-cell stents and three of closed-cell stents had focal restenosis. One closed-cell stent had diffuse proliferative restenosis and one open-cell stent had total occlusion.

CONCLUSION

In-stent restenosis was more common in open-cell stent group, which have larger free cell area than closed-cell stents. Although our radiologic findings promote us to use closed-cell design if 'possible', no difference was detected in terms of clinical outcomes.

Serum Levels of IL-1 β , IL-6, TGF- β , and MMP-9 in Patients Undergoing Carotid Artery Stenting and Regulation of MMP-9 in a New In Vitro Model of THP-1 Cells Activated by Stenting

Inflammation plays an important role in the pathophysiological process after carotid artery stenting (CAS). Monocyte is a significant source of inflammatory cytokines in vascular remodeling. Telmisartan could reduce inflammation. In our study, we first found that, after CAS, the serum IL-1β, IL-6, TGF-β, and MMP-9 levels were significantly increased, but only MMP-9 level was elevated no less than 3 months. Second, we established a new in vitro model, where THP-1 monocytes were treated with the supernatants of human umbilical vein endothelial cells (HUVECs) that were scratched by pipette tips, which mimics monocytes activated by mechanical injury of stenting. The treatment enhanced THP-1 cell adhesion, migration and invasion ability, and the phosphorylation of ERK1/2 and Elk-1 and MMP-9 expression were significantly increased. THP-1 cells pretreated with PD98095 (ERK1/2 inhibitor) attenuated the phosphorylation of ERK1/2 and Elk-1 and upregulation of MMP-9, while pretreatment with telmisartan merely decreased the phosphorylation of Elk-1 and MMP-9 expression. These results suggested that IL-1β, IL-6, TGF-β, and MMP-9 participate in the pathophysiological process after CAS. Our new in vitro model mimics monocytes activated by stenting. MMP-9 expression could be regulated through ERK1/2/Elk-1 pathway, and the protective effects of telmisartan after stenting are partly attributed to its MMP-9 inhibition effects via suppression of Elk-1.

The development of carotid stent material

Endovascular angioplasty with stenting is a promising option for treating carotid artery stenosis. There exist a rapidly increasing number of different stent types with different materials. The bare-metal stent is the most commonly used stent with acceptable results, but it leaves us with the problems of thrombosis and restenosis. The drug-eluting stent is a breakthrough as it has the ability to reduce the restenosis rate, but the problem of late thrombosis still has to be addressed. The biodegradable stent disappears after having served its function. However, restenosis and degradation rates remain to be studied. In this article, we review every stent material with its characteristics, clinical results and complications and point out the standards of an ideal carotid stent.

Valsartan prevents neointimal hyperplasia after carotid artery stenting by suppressing endothelial cell injuries

OBJECTIVES

Restenosis or neointimal hyperplasia remains an important complication after carotid artery stenting (CAS) for carotid artery stenosis. The purpose of this study was to examine if an anti-hypertensive drug, angiotensin receptor blocker (ARB), prevents post-CAS neointimal hyperplasia during the first 1-year period after CAS, and to clarify the possible mechanisms.

METHODS

Hypertension had been treated with a calcium channel blocker (CCB) and/or an ARB, valsartan, by the preference of the neurosurgeon in charge in our department. At admission to perform CAS, patients were assigned to normotensive, valsartan (hypertensive patients treated with valsartan with/without any kind of CCBs), and non-valsartan (hypertensive patients treated with any kind of CCBs without ARBs) groups. Post-CAS neointimal hyperplasia was evaluated by carotid duplex ultrasound imaging in terms of intima-media thickening (IMT), which was performed at pre-CAS and at 90, 180, 270, and 360 days post-CAS. Biomarkers of oxidative stress (8-hydroxy-2'-deoxyguanosine), inflammation (C-reactive protein, tenascin-C) and endothelial cell injury (von Willebrand factor [vWF] antigen) were measured at pre-CAS and at 1, 7, and 180 days post-CAS.

RESULTS

The non-valsartan group (n  =  8) had a higher incidence of maximum in-stent IMT ≧ 1.1 mm compared with the normotensive group (n  =  6). Valsartan (n  =  9) significantly suppressed plasma vWF levels at 7 days post-CAS and decreased the incidence of maximum in-stent IMT ≧ 1.1 mm compared with the non-valsartan group, although clinical parameters were similar between the two groups. Other biomarkers were not significantly different among the three groups.

CONCLUSIONS

These findings suggest that valsartan may prevent post-CAS neointimal hyperplasia possibly by suppressing endothelial cell injury.

Argatroban for preventing occlusion and restenosis after extracranial artery stenting

BACKGROUND/AIMS

Restenosis following extracranial artery stenting is a limitation that affects long-term outcomes. Effective and satisfying pharmacological strategies in preventing restenosis have not been established. This study aimed to evaluate whether argatroban, a direct thrombin inhibitor, could reduce the risk of in-stent restenosis after extracranial artery stenting.

METHODS

One hundred and fourteen patients hospitalized between August 2010 and August 2011 were enrolled. Patients were randomly assigned to argatroban (n = 58) and blank control groups (n = 56). The patients in the argatroban arm were treated with 10 mg of intravenous argatroban twice daily 2 days before and 3 days after the stenting procedures. Patients were followed for 12 months after the procedure. During follow-up, restenosis and target revascularization were analyzed. Recurrent cerebrovascular and cardiovascular events and deaths were also compared between the groups.

RESULTS

One patient in the stenting group withdrew immediately after the procedure due to unsuccessful stenting. Restenosis occurred in 4 patients (7.4%) in the argatroban group and in 11 patients (21.6%) in the control group during the 6- to 9-month angiographic follow-up period (p = 0.032). Nine months after the procedures, argatroban-treated patients had a trend towards a lower incidence of target revascularization compared with the controls (5.4 vs. 13.7%, p = 0.188). No major bleeding events or other adverse events occurred in the argatroban group.

CONCLUSION

This pilot clinical trial is the first that uses argatroban to prevent restenosis in ischemic cerebrovascular disease, and suggests that intravenous administration of argatroban is effective and safe in preventing restenosis after extracranial artery stenting. Larger randomized controlled clinical trials are warranted.

An agent-based model of the response to angioplasty and bare-metal stent deployment in an atherosclerotic blood vessel

PURPOSE

While animal models are widely used to investigate the development of restenosis in blood vessels following an intervention, computational models offer another means for investigating this phenomenon. A computational model of the response of a treated vessel would allow investigators to assess the effects of altering certain vessel- and stent-related variables. The authors aimed to develop a novel computational model of restenosis development following an angioplasty and bare-metal stent implantation in an atherosclerotic vessel using agent-based modeling techniques. The presented model is intended to demonstrate the body's response to the intervention and to explore how different vessel geometries or stent arrangements may affect restenosis development.

METHODS

The model was created on a two-dimensional grid space. It utilizes the post-procedural vessel lumen diameter and stent information as its input parameters. The simulation starting point of the model is an atherosclerotic vessel after an angioplasty and stent implantation procedure. The model subsequently generates the final lumen diameter, percent change in lumen cross-sectional area, time to lumen diameter stabilization, and local concentrations of inflammatory cytokines upon simulation completion. Simulation results were directly compared with the results from serial imaging studies and cytokine levels studies in atherosclerotic patients from the relevant literature.

RESULTS

The final lumen diameter results were all within one standard deviation of the mean lumen diameters reported in the comparison studies. The overlapping-stent simulations yielded results that matched published trends. The cytokine levels remained within the range of physiological levels throughout the simulations.

CONCLUSION

We developed a novel computational model that successfully simulated the development of restenosis in a blood vessel following an angioplasty and bare-metal stent deployment based on the characteristics of the vessel cross-section and stent. A further development of this model could ultimately be used as a predictive tool to depict patient outcomes and inform treatment options.

Plaque morphology detected with Duplex ultrasound before carotid angioplasty and stenting (CAS) is not a predictor of carotid artery in-stent restenosis, a case control study

Background

In-stent restenosis (ISR) is an important factor endangering the long-term safety and efficacy of carotid artery angioplasty and stenting (CAS). It is plausible that soft vulnerable plaques are more likely to be injured during CAS procedure and are therefore more likely to initiate the cascade finally leading to ISR. The aim of this study was to investigate if plaque morphology detected by a simple applicable Duplex ultrasound score before CAS can be used as a predictor for ISR.

Methods

Within a prospectively collected single-centre CAS database of 281 patients (comprising 300 arteries) with high-grade carotid artery stenosis, who underwent CAS between May 2003 and January 2013, we conducted a nested case–control study. Plaque morphology before CAS was analysed by a blinded investigator and each parameter of the Total Plaque Risk Score (TPRS) as well as the whole score was evaluated with regard to its diagnostic validity for ISR.

Results

We analysed the data of 10 patients with ISR and 50 patients without ISR. There were no significant differences with respect to baseline characteristics, vascular risk factors, and degree of stenosis between patients with and without ISR. The duration of follow-up was longer in patients with ISR (p = 0.024) and these patients were more likely to show increased PSV (p = 0.012) immediately after CAS than patients without ISR. Neither individual parameters of the TPRS score nor the score as a whole were suitable as a diagnostic test for ISR development.

Conclusions

In the present study we could demonstrate that the non-contrast enhanced DUS of the pre-interventional plaque formation cannot be used as a predictor for the development of ISR. Evaluating a more sophisticated, but not routinely available approach e.g. by ultrasound based plaque perfusion imaging or CT based plaque analysis could be helpful in the future in order to assess the role of plaque morphology in the context of ISR development.

Age-dependent effects of carotid endarterectomy or stenting on cognitive performance

Although evidence is accumulating that age modifies the risk of carotid angioplasty and stenting (CAS) versus endarterectomy (CEA) for patients with significant carotid stenosis, the impact of age on cognition after either CEA or CAS remains unclear. In this study, we analyzed the effects of age on cognitive performance after either CEA or CAS using a comprehensive neuropsychological test battery with parallel test forms and a control group to exclude a learning effect. The neuropsychological outcomes after revascularization were determined in 19 CAS and 27 CEA patients with severe carotid stenosis. The patients were subdivided according to their median age (<68 years and ≥68 years); 27 healthy subjects served as a control group. In all patients clinical examinations, MRI scans and a neuropsychological test battery that assessed four major cognitive domains were performed immediately before, within 72 h, and 3 months after CEA or CAS. While patients <68 years of age showed no significant cognitive alteration after either CEA or CAS, a significant cognitive decline was observed in patients ≥68 years in both treatment groups (p = 0.001). Notably, this cognitive deterioration persisted in patients after CEA, whereas it was only transient in patients treated with CAS. These results demonstrate an age-dependent effect of CEA and CAS on cognitive functions. In contrast to the recently observed increased clinical complication rates in older subjects after CAS compared with CEA, CEA appears to be associated with a greater, persistent decline in cognitive performance than CAS in this subgroup of patients.

Clinical impact and predictors of carotid artery in-stent restenosis

To assess the incidence and clinical significance as well as predictors of in-stent restenosis (ISR) after carotid artery stenting (CAS) diagnosed with serial duplex sonography investigations. We analyzed 215 CAS procedures that had clinical and serial carotid duplex ultrasound investigations. The incidence of in-stent restenosis (ISR) and periprocedural as well as long-term clinical complications were recorded. The influence of an ISR on clinical complication was analyzed using Kaplan-Meier curves and clinical risk factors for the development of an ISR with multivariate logistic regression. During a median follow-up time of 33.4 months (interquartile range 15.3-53.7) an ISR of ≥70% was detected in 12 (6.1%) of 215 arteries (mean age of 68.1 ± 9.8 years, 71.6% male). The combined stroke and death rate during long-term follow-up was significantly higher in the group with an ISR [odds ratio (OR): 3.59, 95% confidence interval (CI): 1.50-8.59, p = 0.004]. After applying multivariate logistic regression analysis contralateral carotid occlusion (OR 10.11, 95% CI 2.06-49.63, p = 0.004), carotid endarterectomy (CEA) restenosis (OR 8.87, 95% CI 1.68-46.84, p = 0.010) and postprocedural carotid duplex ultrasound with a PSV ≥120 cm/s (OR 6.33, 95% CI 1.27-31.44, p = 0.024) were independent predictors of ISR. ISR after CAS during long-term follow-up is associated with a higher proportion of clinical complications. A close follow-up is suggested especially in those patients with the aforementioned independent predictors of an ISR. Against the background of a lacking established treatment of ISR, these findings should be taken into account when offering CAS as a treatment alternative to CEA.